Sodium 2-mercaptoethanesulfonate, hereinafter referred to as Mesna, has been widely used for several applications mainly as drug and/or formulations in the medical filed. For instance, Mesna has been used as prophylactic agent in reducing the incidence of hemorrhagic cystitis. Mesna has also been used as a mucolytic agent. Additionally, Mesna has been used in surgery, wherein it is known that when applied at a cleavage plane, Mesna breaks the molecular bonds between tissue layers, thereby facilitating tissue separation. Specifically, Mesna breaks disulfide bonds of polypeptide chains and proteins.
Mesna is a white hygroscopic powder with a characteristic odor. The liquid solution in water is highly sensitive to oxidation and rapidly decomposes on contact with oxygen to form di-Mesna also called disulphide Mesna, which is poorly absorbed, particularly in a humid atmosphere.
Most pure Mesna dosage forms used until today are liquid formulations. Since Mesna is very sensitive to oxidation and reacts in the presence of oxygen to form di-Mesna, the aqueous solutions have to be protected against oxygen. In addition, Mesna in liquid form is highly prone to oxidation in presence of metals. Therefore, Mesna solutions are usually sealed into glass ampoules, preferably in low iron glass containers under nitrogen blanket with stabilizers, anti-oxidants and metals chelating agents. Said glass containers are rather expensive. Furthermore, in some procedures, Mesna solutions are needed at different concentrations from those readily available in commercial glass vials, making the use of said vials tedious or inadequate.
When being used, the practitioner has to transfer the solution from glass containers to delivery device or to tube in order to incorporate the solution in the desired application. This step increases the chances of oxidation and contamination of the Mesna solution thereby having reduced Mesna activity or reduced sterility when used, for example in chemically assisted surgery.
Mesna is also available as a more stable crystalline powder from the synthesis (technical Mesna), but this form is not sterile and therefore not suitable to medical applications.
The object of the invention to overcome at least part of the above mentioned problems. The invention aims at providing sterile lyophilized Mesna compositions. This object is achieved in accordance with the invention by a composition and a process as indicated in the claims.